Advice on upgrading TF10 to UE Customs

I have a pair of TF10vi's where the wire has broken twice within a year. Logitech replaced them the first time and this time they're offering to either replace them, or has offered 25% off another pair (of anything). One thing to note is that while I'm happy with the TF10, they haven't been a great fit in my ears and I have to adjust them regularly. I've tried many different tips and currently using the Sony Hybrids, so I'm hoping the Customs would be a better fit.

Do all the UE Customs have better sound quality than the TF10s, or do I have to at least start at a certain level? I'm thinking of using the 25% to pickup the UE 4 Pro, then just buying a replacement cable for the TF10 so I have both of them. Thoughts?

This is definitely one of the options I'm considering. Would a remolded TF10 sound as good, or better than a UE Pro4 (or 5)?

While comfort would be a huge upgrade I think UE4 sound would be a downgrade. Jerry Harvey has been on record saying the custom UE10 is a flatter response TF10. SAme drivers but TF10 mid bass is tuned up a bit for a "funner" sound. I'm not still fuller familiar with UE custom line-up but I think you'd need to go at least to UE7 or higher. But my JH5 has a slight edge over TF10 Pro.

While comfort would be a huge upgrade I think UE4 sound would be a downgrade. Jerry Harvey has been on record saying the custom UE10 is a flatter response TF10. SAme drivers but TF10 mid bass is tuned up a bit for a "funner" sound. I'm not still fuller familiar with UE custom line-up but I think you'd need to go at least to UE7 or higher. But my JH5 has a slight edge over TF10 Pro.

you have that wrong. the ue-10 was out many years before the tf10 was even a thought. The ue-10 were designed as refrence monitors. To be as close to flat and accurate as they could.The ue-7 pro is like the ue-5 pro with a second low end driver. You could compare it kinds like this. The ue-5 pro is to the ue-7 as the ue-10 is to the ue-11 pro. The ue-5c was the consumer audiophile version of the ue-5 pro. Sound signature is quite similar the the westone es2.

you have that wrong. the ue-10 was out many years before the tf10 was even a thought. The ue-10 were designed as refrence monitors. To be as close to flat and accurate as they could.The ue-7 pro is like the ue-5 pro with a second low end driver. You could compare it kinds like this. The ue-5 pro is to the ue-7 as the ue-10 is to the ue-11 pro. The ue-5c was the consumer audiophile version of the ue-5 pro. Sound signature is quite similar the the westone es2.

I'm confused. Where does the TF-10 fit then compared to the UE Pro line?

It does not compare to anything in the custom pro line. There is nothing that sounds like the tf10 pro in the ue custom line.It is solely a consumer universal iem. It is a step up from the super fi line that was out several years ago. There was the super fi 3 and the super fi 5 then a contest came around on head fi when they were designing the tf 10 pro and its name was selected by a member here.Super fi 3 had one driver, 5 had 2 and the tf has 3.